Mobile shovel excavator

ABSTRACT

A MOBILE EXCAVATOR, IN WHICH THE DIGGING TOOL, SHOVEL ARM AND JIB ARE MOUNTED ON A SUPERSTRUCTURE FOR PIVOTED MOVEMENT AND IN A COMMON VERTICAL PLANE, AND THE SUPERSTRUCTURE, IS ROTATABLY MOUNTED ON A WHEELED OR TRACKED VEHICLE FOR MOVEMENT THROUGH A 360* ARC. THE JIB IS ATTACHED TO THE SUPERSTRUCTURE BY MEANS OF A BRACKET WHICH PERMITS PIVOTED MOVEMENT OF THE JIB ABOUT EITHER VERTICAL OR HORIZONTAL AXIS SO THAT NARROW TRENCHES EXTENDING PARALLEL TO THE JIB MAY BE DUG ADJACENT WALLS AND OTHER STRUCTURES.   D R A W I N G

' Feb. 20, 1973 scH E F 3,717,269

MOBILE SHOVEL EXCAVATOR Original Filed Oct. 25, 1968 2 Sheets-Sheet 1 Feb. 20, 1973 scH 3,717,269

MOBILE SHOVEL EXCAVATOR Original Filed Oct. 25, 1968 2 Sheets-Sheet 2 United States Patent Int. Cl. E02f 3/28 US. Cl. 214138 R 1 Claim ABSTRACT OF THE DISCLOSURE A mobile excavator, in which the digging tool, shovel arm and jib are mounted on a superstructure for pivoted movement and in a common vertical plane, and the superstructure, is rotatably mounted on a wheeled or tracked vehicle for movement through a 360 arc. The jib is attached to the .superstructure by. means of a bracket which permits pivoted movement of the jib about either vertical or horizontal axis so that narrow trenches extending parallel to the jib may be dug adjacent walls and other structures.

RELATED APPLICATION This application is a continuation of S. N. 770,657, filed Oct. 25, 1968, now abandoned.

BACKGROUND OF THE INVENTION There are excavators presently used in which transverse suspended plates are situated at either the front or rear of the chassis, and which are removably mounted in a sliding carriage. The disadvantage of this type of apparatus is that they are limited to l80-190 of rotational movement about their vertical axis, and can make use of only 90-95 when working alongside a high wall.

There are also various Well-known supplementary implements. used on conventional excavators, which make possible the production of trenches oriented along the vehicles axis and also about the rotational axis. In this type of apparatus, either the digging tool or the shovel arm are pivoted from the axis of the jib. It is also conventional to mount additional accessories at the side, between the shovel arm and digging tool or between the jib and shovel arm.

With these types of equipment, there is the disadvantage that when operating in a narrow ditch, the mass of the shovel or the length of the shovel arm at the end of which the sides of the trench are situated will hinder the deepening of the ditch. With this type of equipment it is impossible to produce trenches with perpendicular walls by the use of a pivotable shovel arm, because the raising and lowering of the jib causes the axis of the shovel arm to describe an arc and therefore to be pivoted out of the horizontal. A further important disadvantage of conventional mobile excavators lies in the fact that if a structure wall is higher than the excavators body, then the counterweight, which is located some distance away from the vertical pivot axis on the superstructure, will strike the wall.

SUMMARY OF THE INVENTION In order to eliminate these disadvantages the present invention provides a mobile excavator in which the jib pivots about a vertical axis mounted on the superstructure so that the jib may be rotated out of its normal working position (i.e., parallel to the longitudinal axis of the superstructure) to either side, in such a way that a line may be drawn parallel to the jib, through an outermost portion of the digging tool and tangent to the are described by the point on the superstructure spaced furthermost'from the vertical axis of the superstructure as it turns about its vertical axis upon the vehicle. In this way, although the jib, shovel arm and digging tool remain pivotable in their common vertical plane, large trenches can be produced close to or immediately beside any high Wall when the jib is pivoted sideways out of its normal working position parallel to the longitudinal axis of the superstructure.

Of course, the further the axis of the jib is situated out of the arc described by the superstructure, the smaller will be the maximum possible sideways swivel angle of the jib. Therefore, since the reduction of the swivel angle is directly opposed to the object of placing the jib as closely as possible to the center turning point of the superstructure, in order to save balance weight, the maximum. swivel angle of the jib out to either side of the superstructures longitudinal axis should amount to approximately 45 In the present invention, the jib and its lifting cylinder are pivoted on a mounting bracket which is pivotally mounted for movement about a vertical axis situated on the superstructure and which is coupled through an outwardly extending ear to pivoting means. This mounting arrangement lends itself to the use of interchangeable couplings for various larger jibs and/or other apparatus. The pivoting means may take the form of a manually 'operated rod whose outer end is secured by means of a vertical pin through the outwardly extending ear of the mounting bracket, and whose inner end may be attached to the superstructure at any one of several different positions. In this way the position of the jib can be adjusted as desired. Alternatively, the pivoting means could also consist of a hydraulic cylinder whose ends are secured to the outwardly extending ear of the mounting bracket and the superstructure, respectively.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an excavator mounted on a tracked vehicle, in accordance with the invention;

FIG. 2 is a plan view of the excavator of FIG. 1, in which the jib and trench digging tool are situated in the furthermost sideways position, for digging a trench beside a wall;

FIG. 3 is an enlarged schematic side view of the jib mounting with one of the means for side rotation of the mounting; and

FIG. 4 is a schematic plan view of an arrangement similar to FIG. 3 but wherein a hydraulic cylinder is used as the drive means.

DETAILED DESCRIPTION OF THE DRAWINGS FIGS. 1 and 2 show a turning-ring 11 situated on a tracked vehicle 10, which carries a superstructure 12 of a conventional type mobile excavator. The superstructure is mounted on bearings to turn through 360 about vertical axis 13. The counterweight 14 attached to the superstructure serves as equalization for the jib 15, shovel arm 16 and trench tool 17 at the opposite end of the superstructure during operation of the apparatus. The jib 15 is mounted at its lower end on a transverse axis 18 which allows it to have vertical pivotal movement. The horizontal axis 18 of the jib is situated at the lower portion of a mounting bracket 19, at whose upper end 20 there is a lifting cylinder 21 which controls vertical movement of the jib. The mounting bracket 1S rotates on a vertical pin 22 mounted at the front end of the superstructure 12. The journal 23 on the superstructure can consist of a vertical tube in which the pin 22 is arranged for rotational movement; the projecting ends of the pin being secured to the tongues or flanges 24, 25 on the mounting bracket 19.

FIGS. 3 and 4 show an extension of the mounting bracket 19 forming an outwardly extending ear 19a to which the means for sideways movement of the jib is attached. In FIG. 3 this means is shown as a horizontal rod having a bearing pin 26 pivotally received in ear 19a and at its other end a collar 32. A bolt 28 may be inserted in one of the openings 29 (FIG. 2) in the floor of the superstructure and through the collar 32. In this case, the sideways placement of the jib is effected by means of the bolt, e.g. by hand. FIG. 4 shows a hydraulic cylinder 30 used as the drive for sideways movement, whose ends are held at 19a and 31 to the mounting 19 and superstructure 112, respectively.

With reference to FIG. 2, it will be seen that with the mounting bracket at its outermost limit of travel a line T may be drawn parallel to the jib 15 through an outermost portion of the digging tool 17 and tangent to the arc H described by the point on the superstructure 12 (such as point P) spaced furthermost from the vertical axis 13 as the point P rotates about axis 13. It will also be noted from 'FIG. 2 that the maximum swivel angle W of the jib should be limited to approximately 45.

While certain preferred embodiments of the invention have been described for purposes of illustration it will be apparent that modifications thereof will occur to those skilled in the art within the scope of the appended claim.

I claim:

1. An excavator comprising:

(a) a superstructure pivotally mounted on a vehicle for movement about a first vertical axis;

(b) a jib pivotally attached to said superstructure for movement about a second vertical axis;

(c) a digging tool connected to said jib by means of a shovel arm, said digging tool having a width dimension;

(d) a counterweight attached to said superstructure opposite said jib;

(e) said jib having a central position wherein said jib is located in a first vertical plane coincident with both said first and said second vertical axes;

(f) said jib being pivotable to either side of said central position to its outermost limits of travel;

(g) said outermost limits of travel being defined by second and third vertical planes coincident with said second vertical axis and forming approximately a angle with said'first vertical axis; 7

(h) said width of said digging tool and the relative locations of said first and said second .vertical axes being such that with said jib at said outermost limit of travel of approximately 45 a line may be drawn parallel to said jib through an outermost portion of said digging tool and tangent to the are described by a point on said superstructure spaced furthermost [from said first vertical] axis as said point rotates about said first vertical axis.

References Cited UNITED STATES PATENTS 3,121,503 2/1964 Lucas. 3,098,395 7/ 196-3 Haganes. 3,173,561 3/ 1965 Brocklebank et a1. 3,259,259 7/ 1966 Metailler. 3,167,194 1/1965 Davis et al. 2,903,142 9/ 1959 Wills.

FOREIGN PATENTS 971,028 9/1964 Great Britain 214-138 C DRAYTON E. HOFFMAN, Primary Examiner 5 L. J. ORESKY, Assistant Examiner 

